Solution A: KH2PO4 2.300 g Na2HPO4 x 2 H2O 2.900 g Distilled water 50.000 ml Solution B: NH4Cl 1.000 g MgSO4 x 7 H2O 0.500 g CaCl2 x 2 H2O 0.010 g MnCl2 x 4 H2O 0.005 g NaVO3 x H2O 0.005 g Trace element sol. SL-6 (see medium 27) 5.000 ml Distilled water 920.000 ml Agar (if necessary) 20.000 g Solution C: Ferric ammonium citrate 0.050 g Distilled water 20.000 ml Solutions A, B, C are autoclaved separately for 15 min at 121?C, cooled down to 50?C and then mixed aseptically with 5.0 ml filter-sterilized standard vitamin solution (see below).The final pH of this medium should be 6.8 without adjustment. For chemolithotrophic growth incubate the culture under an atmosphere of 2% (v/v) O2, 10% CO2, 60% H2 and 28% N2. For heterotrophic growth supplement the mineral medium with an appropriate carbon source (0.2% carbohydrate or 0.1% organic acid). For growth on nitrogen-free medium, omit NH4Cl and incubate the culture under an atmosphere of 2% (v/v) O2, 10% CO2, 10% H2 and 78% N2 or heterotrophically under 2% (v/v) O2 and 98% N2. For more details see Ref. 1515 and Ref. 3363. Standard vitamin solution: Riboflavin 10.000 mg Thiamine-HCl x 2 H2O 50.000 mg Nicotinic acid 50.000 mg Pyridoxine-HCl 50.000 mg Ca-pantothenate 50.000 mg Biotin 0.100 mg Folic acid 0.200 mg Vitamin B12 1.000 mg Distilled water 100.000 ml
